Expansion joint for pipe lines



Feb- 2, 1.954 w. l.. KINGSTON EXPANSION JOINT FOR PIPE LINES Filed Aug. l0, 1951 ln'uen lo r QNIA |l|l 19% W Allurny Patented Feb. 2, k1954 UNITED STATES PATENT OFFICE EXPAN SION JOINT F R PIPE LINES Willard. L. Kingston, Lucerne, Calif.

Application August 10, 1951, Serial No. 241,207

(Cl. 13S-27) 4 Claims. l Y

This invention relates to a novel expansible joint particularly adapted for use in pipe lines of water conduits and has for its primary object to provide a joint having an expansible chamber which is capable of being enlarged by an excess pressure created therein by the freezing of water to prevent bursting of the pipe line in sub-freezing weather.

More particularly, it is an aim of the present invention to provide a novel expansible joint capable of being used in long pipe lines due to the fact that the joint is not extended by enlargement of the expansion chamber thereby adapting the expansion joint to water conduits and other pipe lines generally and providing a joint which may be readily interposed at any desired point in a pipe line.

Still another object of the invention is to provide an expansible joint having a sealing means which is held in a sealing position partially by the pressure within the expansion joint and partially by an expansion spring wherebythe electiveness of the sealing means will be increased as the pressure in the expansion joint increases to thereby eiectively prevent leakage past the seal without seriously hampering movement of the seal relatively to the stationary parts of the expansion joint.

Still a further object of the invention is to provide an expansion joint of extremely simpleconstruction which is capable of being economically manufactured yet which will be extremely enicient and durable for accomplishing its intended purpose.

v Various other objects and advantagesv of the invention will hereinafter become more fully apparent from the following descriptionY of the drawing, illustrating a presently preferred embodiment thereof, and wherein:

Figure l is a longitudinal, substantially central sectional View partly inelevation illustrating the expansion joint in an applied position and as it will normally appear when not subjected to excessive pressure;

Figure 2 is a longitudinal sectional View; partly in side elevation showing the expansion joint with the parts as they will appear when the joint is subjected to an excessive pressure as by the freezing of a liquid contained therein, and

Figure 3 is a cross sectional view of the expansion joint taken substantially along a plane as indieated by the line 3-3 of Figure 2.

Referring more specifically to the drawing, the novel expansion joint in its entirety is designated generally and is illustrated in Figures 1 and 2 interposed in a portion of a pipe line, such as a 2 water conduit of a city water system a portion only of which has been shown by the adjacent ends of two spaced pipe sections 6 and 'I.

The expansion joint 5 includes a length of pipe 8 of substantially larger internal and external diameters than that of the pipe sections 6 and l. One end of the pipe 8 is threaded into the enlarged end of a reducer coupling 9 and the opposite end 0f the pipe 8 is similarly threaded into the enlarged end of a similar pipe reducer coupling I0. The reducer couplings 9 and Ill are substantially bell-shaped and have outer restricted internally threaded ends II and I2, respectively. The end of the pipe section 6 disposed adjacent the pipe section 'I is threaded into the outer half of the reduced end II of the coupling and the adjacent end of the pipe section I is threaded into and thereby similarly coupled to the reduced end I2 and the pipe coupling IIJ.

The expansion joint 5 also includes a length of pipe I3 of substantially the same internal and external diameters as the pipe sections 6 and 1 and which has an externally threaded end I4 which is threadedly engaged in the inner half of the restricted coupling end I I for supporting the pipe I3 on the coupling 9 and within said coupling and the pipe 8. The pipe I3 is disposed axially of the pipe 8 and has an opposite externally threaded end I5 which terminates in spaced relationship to the ends of the pipe 8.

The pipe I3 extends through a substantially rigid washer I6 which is disposed in and abuts against the intermediate portion of the coupling 9 and which forms a seat for one end of an expansion coiled spring I1 which is disposed around the pipe I3 and within the pipe 8. A nut I8 is threadedly mounted on the threaded pipe portion I5. A pair of rigid washers I9 and 26 is slidably mounted on the pipe I3 and within the pipe 8 between the nut I8 and spring I1 and with the washer I9 disposed nearest the nut I8. A thicker, rigid washer 2| is slidably mounted on the pipe I3 within the pipe 8 between the washer 2D and spring I'I and forms a seat for the end of the spring I1 disposed remote to the spring seat I6. An expansible sealing washer or gasket 22 is mounted on the pipe I3 and Within the pipe 8 between the washers I9 and 20 and is preferably formed of rubber and has its periphery bevelled from opposite sides thereof to provide an annular ridge 23 which bears against the inner surface of the pipe 8. The bore of the washer or gasket 22 is similarly bevelled from opposite sides thereof to form a centrally disposed rib or ridge 24 which bears against the outer side of the pipe I3.

The reducer coupling I0 and the portion of the pipe 8 disposed between said coupling I0 and the washer i9 constitutes the expansion chamber 25 of the expansion joint 5. The spring l1 is of sufficient strength to withstand the normal pressure of the water or other liquid, not shown, in the expansion chamber 25 and will accordingly retain the washers i9, 2t and 2i and the sealing washer 22 in the positions as illustrated in Figure l and with the washer 'I9 bearing against'the nut i8. The pressure of the spring l? with the parts thus disposed is sufficient to compress the washer 22 between the washers W9 and 2G with sucient force to .causethewasher 22 to be expanded radially inwardly 'and 'outwardly so that its peripheral portionlZS-willseat against the inner surface of the pipe 8 and its bore portion 2li will seat against the outerrsurface or" the pipe i3 each sumciently tight .toiprevent leakage of the liquid from the expansion chamber 25 into the chamber dSie ofthe joint 5,

which contains the spring il. V1shenthe jint vis subjected to sub-freezing temperature causfing a freezing of Ythe liquid in the expansion l chamber the freezing of the liquid will produce an 4expansion thereof, the force of which will be exerted at the point or" least'resistance i. e. against the washer i9 for displacing the vwashers ig, 2d and 2i and the sealing washeror gasket 22 from left to right from their positions of Figure 1 to or partially to or beyond the posi- -tions of said parts as seen in Figure 2, to thereby enlarge the chamber 25 to accommodate 'the necessary expansion caused by the freezing without bursting the pipe line adjacent the joint or any part of the joint. The pipe i is provided with a vent port if adjacent the coupling 9 through which air can escape from the chamber 26 as the parts move from their positions of VFigure 1 to their positions of Figure 2. it will also be readily apparent that as the pressure builds up in the chamber as the result oi the freezing of a liquid contained therein so as to force the washers and sealing gasket from left to right,

"that this pressure will impinge against the washer i9 so that greater pressure willbe exerted by the washers iii and 2) on the sealing gasket 22 as the pressure of the spring il is also increased `as the parts move to the right. This wall cause the gasket 22 to be more tightly sealed against the bore of the pipe G and the periphery of the pipe lto prevent escape ofthe liquid from the chamber 25 to the chamber 2i? asthe pressure in the chamber is increased. When the ice melts in the chain er 2e and the pressure fis thereby diminished, the spring i? will return the washers and sealing gasket 'to their positions of Figure l and air will enter the chamber 2E through the vent port 2i' to prevent a vacuum being created therein.

lVarious modifications and changes 'are contemplated and may obviously be resorted to,V without departing from 'the spirit or scope of the invention as hereinafter defined by the appended claims.

I claim as my invention:

1 The combination with adjacent ends of pipe sections forming a part of a pipe line, ofan eX- pansion joint interposed in the pipe line includ- Y ing a pipe of larger internal and external diameters than said pipe sections and disposed therebetween, restrictor couplings connecting said pipe sections to the adjacent ends of the pipe, an

inner pipe disposed within said first mentioned 'pipe and substantially axially thereof having one end secured to the 'restricted Vendofronenfthe 4 couplings and an opposite end disposed intermediate of the ends of the first mentioned pipe, a

stop removably mounted on the last mentioned end of the inner pipe, a spring stop mounted on said inner pipe and seated in said aforementioned restrictor coupling, an expansion spring disposed around said inner pipe between the spring stop and said removable stop, a pair of rigid washers :slidably disposed on said inner pipebetween said .expansionzspring andsaid removable stop, and a sealing washer or gasket slidably disposed on fthe inner pipe between the washers of said pair of washers and compressed by the pressure of said-'springbetween said washers for expanding ethe'sealinggasket radially in both directions into sealing engagement with the periphery of the iinn'erpipe andthe bore of said first mentioned pipe-.to form a chamber between the inner pipe and said rst mentioned pipe and between said sealing washer and said aforementioned restrctor .'coupling'which chamber is sealed off from the 'remainder `of Ysaid rst mentioned pipe, the portion'of said rst mentioned pipe located between the Vsealinggasket and the other restrictor coupling forming an expansion chamber, said pair of washers'and'the sealing gasket being displaced longitudinally-of the pipe away from the removable stop by an increased pressure in the eX- vpansion chamber and against the action of said VVas the expansion chamber is enlarged by the increased Vtension on the expansion spring and the Vincreased pressure exerted against one of said rigid washers by the pressure within the eX- pansion chamber to more effectively seal on the n"expansion chamber from the chamber of the expansion joint having the vent port.

3. An expansion joint as in claim l, said sealing gasket having a periphery bevelled on opposite sides thereof forming an annular ridge :disposed in contact with the boreof said iirst mentioned pipe. Y Y

'4. An expansion joint asin claim 3, the bore of said sealing gasket being lbevelled on opposite sides thereof to form a continuous internal rib, said internal rib contacting the peripheryrof said inner pipe and combining with said annular ridge of the sealing gasket to permit the sealing gasket to slide more readily Ylongitudinally of the expansion joint. Y

VVILLARD L. KINGSTON.

References Citedin the file of this patent -UNITED'STATES PATENTS Number Name Date 594g0'70 Fahr Nov. 23, 1897 V*696,277 Sponseller et al Mar. 25, 1962 l'881,687 Hoffner Mar. 10, 19GB 966,748 Honecker Aug. 9, 191() 1,536,531 .'Schermann May 5, 1925 2,056,076 Le Blanc Sept. 29, 1936 FOREIGN Aim'rnirrs -Number Country Date 73,194 Great Britain Nov. 9, 1945 

